1. Field of the Invention
The instant invention relates to an apparatus for collecting monocytes from animals.
2. Description of the Prior Art
Yield of monocytes obtainable from peritoneal cavity of unstimulated animals is too low to make use of these monocytes. See Stuart, A. E., Habeshaw, J. A. and Davidson, A. E. in "Handbook of Experimental Immunology", p. 24.1 (Weir, Editor), Blackwell Scientific Publications, Osney Mead, Oxford, England, 1976. In man and other veterbrates, pulmonary monocytes can be obtained from unstimulated subjects by bronchopulmonary lavage. However, the procedure is considered to be relatively difficult, each monocyte collection requires separate isolation procedures, and the monocyte yields are relatively low. See Finley, T. N. and Ladman, A. J. New England Journal Medicine, 286, p. 223-227, 1972.
D. H. Burrin, et al., in British Experimental Pathology 47, 70-75, 1966 disclosed the isolation of monocytes from bovine blood by sedimentation techniques. The monocytes were found to be phagocytic for Brucella abortus. The purity and yield of monocytes were very poor because monocytes represent only 1% of the white blood cell population in the bovine Bovine monocytes were isolated from blood adherence to glass. However the yields of monocytes obtained by this method are poor, even with the use of large volumes of blood. See Fitzgeorge, R. P. et al., British Journal of Experimental Pathology 48, 522-528, 1967.
Mononuclear cells called monocytes have numerous biological functions are very important to immunity and defense.
The following references provide a ready review of pertinent information and data with respect to monocytes and their vital function in animals: The Immunobiology of Macrophage, 1976, compiled by Dr. D. S. Nelson, ed., Academic Press, N.Y.; The Handbook of Experimental Immunology, compiled by Dr. D. M. Weir, ed., 1976, Blackwell Scientific Publications, Oxford, England; The Manual of Clinical Immunology, compiled by Drs. N. R. Rose and H. Friedman, eds., 1976, and The American Society of Microbiology, Washington, D.C.
The yield of monocytes from the peritoneal cavity can be greatly increased by the use of inducing agents. The inducing agents are injected into the peritoneal cavity prior to harvesting monocyte exudate from the stimulated animal. The animal usually needs to be killed prior to monocyte harvesting, thereby limiting the kind of animal used. The best inducing agents are those that provoke an exudate rich in monocytes and that are biodegradable, leaving no trace in the cultured monocytes. The use of chemical inducing agents such as serum, glycogen, mineral oil, protease peptone broth, thioglycollate, casein, etc. have many drawbacks. See Stuart, A. E., Habeshaw, J. A., and Davidson, A. E. in "Handbook of Experimental Immunology", p. 24.2 (Weir, Editor), Blackwell Scientific Publications, Oxford, England, 1976.
Monocytes can be collected and purified from chickens by implantation of polysterene discs into the peritoneal cavity. The discs were removed after 4 days from the sacrificed chickens and transferred to petri dishes containing culture medium. The yield of monocytes was 3 to 4.times.10.sup.6 /chicken with a purity of 80%. The use of discs caused the stimulation of monocytes without the drawbacks of inducing agents. However, the yield and purity of monocytes were low. In addition, the animal must be killed prior to removal of the implanted discs and the harvest of monocytes. See Micalizio, S. and Della Bruna, C. Experimentia 5191,1109,1975.
Diffusion chambers of lucite rings with various membranes have been used to study monocytes without the use of inducing agents. The diffusion chambers were implanted into the peritoneal cavity of animals primarily to study the function of various cells rather than the collection of monocytes. Removal of the diffusion chambers from sacrificed animals was required to recover cell populations. See Shelton, E. and Rice, M. E. American J. Anatomy 105, 281, 341, 1959.